<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <script>
   //假设d是范围内的空对象
    var d={};
   //是用下面代码完成了什么？
    ['zabra','horse'].forEach(function(k){
        d[k]=undefined;
    })
     </script>
</body>
</html> 









